Non-skid grating



July 14, 1964 R. B. LEE 3,140,644

NON-SKID GRATING Filed May 28, 1962 2 Sheets-Sheet 1 10 H6. 2 INVENTOR.

ROYAL 8. LEE

July 14, 1964 R. B. LEE 3,140,644

NON-SKID GRATING Filed May 28, 1962 2 Sheets-Sheet 2 gmlllllk L 20 2O 24 O 20 FIG. 5

INVENTOR. ROYAL B. LEE

mlm

United States Patent 3,140,644 NON-SKID GRATING Royal B. Lee, 840 Medford St., El Cajon, Calif. Filed May 28, 1962, Ser. No. 198,076 6 Claims. (Cl. 94-30) The present invention relates generally to floor and tread structures and more particularly to a non-skid grat- The primary object of this invention is to provide a non-skid grating incorporating a reticulated arrangement of upstanding tabs forming a raised tread surface having frictional gripping qualities in any direction.

Another object of this invention is to provide a nonskid grating which can be cut or stamped from a single sheet of material and formed by simple bending, the finished grating having longitudinal stiffening ribs and transverse reinforcing flanges.

Another object of this invention is to provide a nonskid grating which is self-supporting and does not specifically require bolting, welding, or any other type of securement to maintain its form.

A further object of this invention is to provide a nonskid grating which can be made in a variety of sizes for floors, stair treads, or insert panels in floor structures, and other uses.

Finally, it is an object to provide a non-skid grating of the aforementioned character which is simple and convenient to manufacture and install and which will give generally eflicient and durable service.

With these and other objects definitely in view, this invention consists in the novel construction, combination and arrangement of elements and portions, as will be hereinafter fully described in the specification, particularly pointed out in the claims, and illustrated in the drawings which form a material part of this disclosure, and in Which:

FIGURE 1 is a perspective view of a portion of the grating;

FIGURE 2 is a plan view of the blank sheet ready for forming;

FIGURE 3 is a sectional view taken on line 3-3 of FIGURE 1;

FIGURE 4 is a sectional view taken on line 44 of FIGURE 3; and

FIGURE 5 is a top plan view of a portion of complete grating.

In the following explanation and claims the terms longitudinal and transverse will be used somewhat arbitrarily in the interest of simplicity and clarity, although it is conceived that the grating will usually, although not necessarily, be constructed in oblong sections for installation with ribs formed by downward bending, as herein: after more fully described, extending longitudinally of the oblong sections.

The grating is made from a singleflat sheet of metal 10, as in FIGURE 2, all structure being made by simple cuts and bends. In layout, the sheet is divided into spaced parallel rows of equal rectangular areas having their long dimensions transversely of the rows, the rectangles being indicated as substantially bounded by single broken lines 11 and 12 which represent downward bends. Between the rows of rectangles are stiffener portions 14, along the center lines of which are indicated double broken lines 16 representing upward bends. Every alternate rectangle in a particular row has at its ends inwardly extending opposed arcuate cuts 18 forming tabs 20 and at the center of the sides of each such rectangle are outwardly extending opposed arcuate cuts 22 forming tabs 24. In addition the arcuate cuts 18, in each said alternate rectangle, are connected by a central transverse cut 26 bisecting the mentioned rectangle and forming 3,140,644 Patented July 14, 1964 a pair of flanges 28. It should be noted that bend lines 11 and 12 do not extend chordally across tabs 20 and 24, which are not to be bent. Each row of rectangles is treated in a similar manner but the bisected rectangles are longitudinally staggered in adjacent rows.

The grating is formed by making the longitudinal bends downwardly along bend lines 11 and upwardly along bend lines 16. This forms the stiffener portions 14 into return folded longitudinal ribs 30, which may be considered primary load bearing members, the tabs 20 being allowed to remain coplanar with said ribs and these tabs therefore project upwardly. The flanges 28 are then bent downwardly along bend lines 12, allowing tabs 24 to remain coplanar With the flanges and project upwardly, as in FIGURES 3 and 4. In the resultant structure the top face of the grating is composed of alternate rectangular openings and planar platform portions 32, the flanges 28 depending on opposite sides of said platform portions. Due to the staggering of the cut out portions in adjacent rows the tabs Ztl form continuous rows along the top of ribs 30, while tabs 24 are spaced in transverse rows, in a reticulated pattern. The tabs 20 and 24 thus constitute small scraper type elements arranged orthogonally to provide friction in any direction against the soles of shoes or boots.

For mounting purposes the stiffener portions along one or both of the outside edges of the grating may be bent to provide inwardly turned attachment flanges 34, as indicated in broken line in FIGURE 3, instead of being return folded. In wide, multiple grating assemblies the return folded ribs 30 of adjoining panels may be interconnected, or the attachment flanges 34 provided on some grating panels may be used for tie down purposes.

If the sheet material from which the grating is made is of sufiicient thickness and strength, the arrangement of the folded portions will be of ample rigidity when the grating is properly secured to suitable supports. However, for particularly heavy duty use the double walls of the ribs 30 may be welded together at intervals for additional strength. In any event, no complex shaping apparatus is necessary and there are no separate parts to 'be aligned and assembled. The simple structure allows considerable latitude in the steps of the manufacturing process to suit available equipment. The arcuate tabs 20 and 24 are particularly effective in regard to strength, since they have a maximum base area of connection with the main structure, but have no sharp corners to become bent or broken off.

The grating can be made in various sizes and used singly as stair treads or inserts in floors, or can be assembled to form entire floors, walkways and the like. Many different types of supporting structures and attachment means may be used. In a modified embodiment, a nosing or plain area may be provided along one or both longitudinal edges of the grating. This may be accomplished by merely increasing the width of the flat portion at either edge of the grating. An abrasive nosing plate could be secured when desired.

In order to conserve material and to reduce weight, the ribs 30 in the intermediate portions of the grating may be of lesser vertical dimension than the ribs at the outside longitudinal edges of the grating. This is accomplished by reducing the width of the corresponding stiffener portions 14 prior to the bending thereof into rib form. The depth of the intermediate ribs tends to be fixed or dictated by strength considerations but the outside ribs could in some instances be of lesser depth when, for example, these outside ribs rest on strong sills or the like. It is also conceived that a grating of similar configuration can be achieved by molding from powdered metal or non-metallic material.

It is understood that still other minor variations from the form of the invention disclosed herein may be made without departure from the spirit and scope of the invention, and that the specification and drawings are to be considered as merely illustrative rather than limiting.

I claim: 1. A non-skid grating, comprising: a unitary sheet element having a plurality of spaced,

longitudinal return folded ribs; rows of longitudinally spaced, substantially coplanar platform portions between said ribs and having openings therebetween; said ribs having upwardly projecting tabs at the ends of said openings; and said platform portions having upwardly projecting tabs at the sides thereof normal to said first mentioned tabs and constituting therewith a reticulated array of non-skid elements. 2. A non-skid grating according to claim 1, wherein said tabs are substantially arcuate.

3. A non-skid grating, comprising: a unitary sheet element having a plurality of spaced,

longitudinal return folded ribs; rows of longitudinally spaced, substantially coplanar platform portions between said ribs and having openings therebetween; said ribs having upwardly projecting tabs at the ends of said openings; said platform portions having downwardly extending flanges along opposite sides thereof between said ribs; and said platform portions having upwardly projecting tabs integral with said flanges normal to said first mentioned tabs and constituting therewith a reticulated array of non-skid elements. 4. A non-skid grating, comprising: a unitary sheet element having a plurality of spaced,

longitudinal return folded ribs;

rows of longitudinally spaced, substantially coplanar platform portions between said ribs and having openings therebetween;

said ribs having upwardly projecting tabs at the ends of said openings; said platform portions having downwardly extending flanges along opposite sides thereof between said ribs;

said platform portions having upwardly projecting tabs integral with said flanges normal to said first mentioned tabs and constituting therewith a reticulated array of non-skid elements;

the platform portions being longitudinally staggered in adjacent rows, whereby said first mentioned tabs form continuous longitudinal rows.

5. A non-skid grating according to claim 4, wherein said ribs at the outer edges of the grating have inwardly turned attachment flanges.

6. A non-skid grating according to claim 4 wherein said ribs are of different vertical dimension, the depth of the ribs at the longitudinal edges of the grating being determined to accommodate the grating to the particular supporting structure whereon the grating is to rest, the depth of the remaining intermediate ribs being determined solely by strength requirements thereof as primary load bearing members, whereby the weight of the grating and the amount of material used in fabrication thereof can be minimized.

References Cited in the file of this patent UNITED STATES PATENTS 1,154,254 Lachman Sept. 21, 1915 1,594,609 Frease Aug. 3, 1926 1,875,188 Williams Aug. 30, 1932 2,558,185 Leisen June 26, 1951 2,781,703 Nagin Feb. 19, 1957 2,828,843 Hill Apr. 1, 1958 3,046,617 Grayboff July 31, 1962 

1. A NON-SKID GRATING, COMPRISING: A UNITARY SHEET ELEMENT HAVING A PLURALITY OF SPACED, LONGITUDINAL RETURN FOLDED RIBS; ROWS OF LONGITUDINALLY SPACED, SUBSTANTIALLY COPLANAR PLATFORM PORTIONS BETWEEN SAID RIBS AND HAVING OPENINGS THEREBETWEEN; SAID RIBS HAVING UPWARDLY PROJECTING TABS AT THE ENDS OF SAID OPENINGS; AND SAID PLATFORM PORTIONS HAVING UPWARDLY PROJECTING TABS AT THE SIDES THEREOF NORMAL TO SAID FIRST MENTIONED TABS AND CONSTITUTING THEREWITH A RETICULATED ARRAY OF NON-SKID ELEMENTS. 